<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script type="text/javascript">
			console.log('Hello JS!');
			// alert('Hello');
			var num = 3;
			var str = '10';
			console.log(num + str);// 310
			console.log(num + parseInt(str));// 13
			console.log(parseInt(3.99));// 3 向下取整
		</script>
	</head>
	<body>
	</body>
</html>
